The present invention relates to an electrochemical generator element successively comprising a first electrode layer of one polarity, a first electrolyte layer, an electrode layer of a reverse polarity, a second electrolyte layer and a second electrode layer of said polarity, said electrode layers of said polarity being connected by a connection in parallel, the element further comprising current collectors, connected to the electrode layers of said polarity.
The invention is applicable, for example, to lithium-polymer electrochemical batteries for electric vehicles or steady-state applications.
Electrochemical generators with lithium having a polymer electrolyte are known. Such generators generally comprise elements consisting of two half-elements electrically connected in parallel.
Each half-element consists of a cathode layer which is applied via an electrolyte layer onto one of the two faces of a lithium layer. The current is drawn by current collectors arranged on the free surface of the cathodes and of the collecting leads connected to the lithium layer.
The cathode layers on the two sides of the lithium layer have the same thickness (FIG. 1). To increase the specific energy (energy per unit mass) of such an electrochemical generator, the thickness, which has the same value for both cathode layers, is increased. Correspondingly, the thickness of the lithium layer is also increased. This has the effect that the maximum specific power (power per unit mass) decreases as the resistance of the element increases.